From 0754f0dda52c1b6870732be98b7697be5f4ba9cd Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@sliepen.org>
Date: Tue, 29 Jul 2014 16:51:11 +0200
Subject: [PATCH] Remove errno and errstr from meshlink_handle_t, add
 thread-local meshlink_errno.

Errors can happen outside of the context of a meshlink handle, for example
if meshlink_open() itself fails. Furthermore, errstr can always be derived
from errno, so it is redundant.
---
 examples/chat.c    |  8 ++++----
 examples/chatpp.cc | 10 +++++-----
 src/meshlink++.h   |  4 ++++
 src/meshlink.c     |  2 ++
 src/meshlink.h     |  5 +++--
 5 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/examples/chat.c b/examples/chat.c
index 70d17d7d..1c07e422 100644
--- a/examples/chat.c
+++ b/examples/chat.c
@@ -42,7 +42,7 @@ static void parse_command(meshlink_handle_t *mesh, char *buf) {
 
 		invitation = meshlink_invite(mesh, arg);
 		if(!invitation) {
-			fprintf(stderr, "Could not invite '%s': %s\n", arg, mesh->errstr);
+			fprintf(stderr, "Could not invite '%s': %s\n", arg, meshlink_strerror(meshlink_errno));
 			return;
 		}
 
@@ -55,7 +55,7 @@ static void parse_command(meshlink_handle_t *mesh, char *buf) {
 		}
 
 		if(!meshlink_join(mesh, arg))
-			fprintf(stderr, "Could not join using invitation: %s\n", mesh->errstr);
+			fprintf(stderr, "Could not join using invitation: %s\n", meshlink_strerror(meshlink_errno));
 		else
 			fprintf(stderr, "Invitation accepted!\n");
 	} else if(!strcasecmp(buf, "kick")) {
@@ -164,7 +164,7 @@ static void parse_input(meshlink_handle_t *mesh, char *buf) {
 	}
 
 	if(!meshlink_send(mesh, destination, msg, strlen(msg) + 1)) {
-		fprintf(stderr, "Could not send message to '%s': %s\n", destination->name, mesh->errstr);
+		fprintf(stderr, "Could not send message to '%s': %s\n", destination->name, meshlink_strerror(meshlink_errno));
 		return;
 	}
 
@@ -193,7 +193,7 @@ int main(int argc, char *argv[]) {
 	meshlink_set_log_cb(mesh, MESHLINK_INFO, log_message);
 
 	if(!meshlink_start(mesh)) {
-		fprintf(stderr, "Could not start MeshLink: %s\n", mesh->errstr);
+		fprintf(stderr, "Could not start MeshLink: %s\n", meshlink_strerror(meshlink_errno));
 		return 1;
 	}
 
diff --git a/examples/chatpp.cc b/examples/chatpp.cc
index 864a3e80..73ced3c6 100644
--- a/examples/chatpp.cc
+++ b/examples/chatpp.cc
@@ -42,7 +42,7 @@ static void parse_command(meshlink::mesh *mesh, char *buf) {
 
 		invitation = mesh->invite(arg);
 		if(!invitation) {
-			fprintf(stderr, "Could not invite '%s': %s\n", arg, mesh->errstr);
+			fprintf(stderr, "Could not invite '%s': %s\n", arg, meshlink::strerror());
 			return;
 		}
 
@@ -55,7 +55,7 @@ static void parse_command(meshlink::mesh *mesh, char *buf) {
 		}
 
 		if(!mesh->join(arg))
-			fprintf(stderr, "Could not join using invitation: %s\n", mesh->errstr);
+			fprintf(stderr, "Could not join using invitation: %s\n", meshlink::strerror());
 		else
 			fprintf(stderr, "Invitation accepted!\n");
 	} else if(!strcasecmp(buf, "kick")) {
@@ -81,7 +81,7 @@ static void parse_command(meshlink::mesh *mesh, char *buf) {
 				fprintf(stderr, "No nodes known!\n");
 			} else {
 				printf("Known nodes:");
-				for(int i = 0; i < n && i < 100; i++)
+				for(size_t i = 0; i < n && i < 100; i++)
 					printf(" %s", nodes[i]->name);
 				if(n > 100)
 					printf(" (and %zu more)", n - 100);
@@ -164,7 +164,7 @@ static void parse_input(meshlink::mesh *mesh, char *buf) {
 	}
 
 	if(!mesh->send(destination, msg, strlen(msg) + 1)) {
-		fprintf(stderr, "Could not send message to '%s': %s\n", destination->name, mesh->errstr);
+		fprintf(stderr, "Could not send message to '%s': %s\n", destination->name, meshlink::strerror());
 		return;
 	}
 
@@ -193,7 +193,7 @@ int main(int argc, char *argv[]) {
 	mesh->set_log_cb(MESHLINK_INFO, log_message);
 
 	if(!mesh->start()) {
-		fprintf(stderr, "Could not start MeshLink: %s\n", mesh->errstr);
+		fprintf(stderr, "Could not start MeshLink: %s\n", meshlink::strerror());
 		return 1;
 	}
 
diff --git a/src/meshlink++.h b/src/meshlink++.h
index c8bdc2f9..a357cca6 100644
--- a/src/meshlink++.h
+++ b/src/meshlink++.h
@@ -387,6 +387,10 @@ namespace meshlink {
 	static void close(mesh *mesh) {
 		meshlink_close(mesh);
 	}
+
+	static const char *strerror(errno_t err = meshlink_errno) {
+		return meshlink_strerror(err);
+	}
 };
 
 #endif // MESHLINKPP_H
diff --git a/src/meshlink.c b/src/meshlink.c
index 23fe1dc4..6d6b77f9 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -44,6 +44,8 @@ typedef struct {
 #define MSG_NOSIGNAL 0
 #endif
 
+__thread meshlink_errno_t meshlink_errno;
+
 //TODO: this can go away completely
 const var_t variables[] = {
 	/* Server configuration */
diff --git a/src/meshlink.h b/src/meshlink.h
index b54e961e..018ba9a3 100644
--- a/src/meshlink.h
+++ b/src/meshlink.h
@@ -48,11 +48,12 @@ typedef enum {
 	MESHLINK_ENOENT, ///< Node is not known
 } meshlink_errno_t;
 
+/// A variable holding the last encountered error from MeshLink.
+extern __thread meshlink_errno_t meshlink_errno;
+
 #ifndef MESHLINK_INTERNAL_H
 
 struct meshlink_handle {
-	meshlink_errno_t meshlink_errno; ///< Code of the last encountered error.
-	const char *errstr;              ///< Textual representation of most recent error encountered.
 };
 
 struct meshlink_node {
-- 
2.39.2